This application claims the priority of German patent 197 31 331.0-12, filed Jul. 22, 1997, the disclosure of which is expressly incorporated by reference herein.
The invention relates to a drive shaft for transmitting power from the transmission to the rear axle of a motor vehicle, for example, from ATZ Automobiltechnische Zeitschrift 99 (1997), Volume 5, Pages 256 to 263. This article relates to light-weight construction in the transmission line and, among other things, also discusses light-weight construction measures on a drive shaft in a concrete embodiment. After a discussion of various conceivable variants, the specific drive shaft is introduced. In its case, the light-weight construction is essentially implemented by using aluminum as the light-weight construction material. On the transmission side, the known drive shaft has a disk joint; in the center, it has a cardan joint; and in the rear, it has an axially inflexible, homokinetic joint. The required length compensation of the drive shaft is integrated into the center cardan joint and is utilized also for mounting the center bearing.
It is an object of the invention to improve a drive shaft such that it can be produced in a particularly light manner and at reasonable cost.
These and other objects have been achieved according to the present invention by providing a two-part drive shaft for transmitting power from a transmission to a rear axle of a motor vehicle, comprising: a first shaft section which originates from the transmission and is constructed as a hollow shaft, said first shaft section having a pivot bearing on an end located away from the transmission; a center cardan joint arranged proximate the end of the pivot bearing located away from the transmission; a second shaft section which adjoins the center cardan joint and is constructed as a hollow shaft; and a rearward cardan joint arranged on an end of the second shaft section for connection to an input shaft of a differential gear of the rear axle, said rearward cardan joint being constructed as a homokinetic cardan joint permitting an axial length compensation, said first shaft section being axially divided proximate the pivot bearing for permitting a mounting of the bearing element constructed as a closed ring-shaped roller bearing, the center cardan joint being constructed as a disk joint with a flexible ring disk arranged perpendicularly to an axis of rotation of the shaft, said flexible ring disk being held between a plurality of flanges provided on the adjoining shaft sections, the axial division of the first shaft section being closable by a connection construction which radially is built up toward the interior.
These and other objects have also been achieved according to the present invention by providing a drive shaft for a motor vehicle, comprising: a first hollow shaft section to be coupled to a transmission of the motor vehicle, said first hollow section being divided into two separate parts at an axial division proximate a location for a supporting bearing for the first shaft section; a second hollow shaft section to be coupled to a differential of the motor vehicle; a disk joint interposed between said first and second hollow shaft sections; and a connector for holding said two separate parts of the first hollow shaft section together, said connector being threadedly engaged with a first of said two separate parts, said connector defining a sloped shoulder which engages a corresponding sloped shoulder of a second of said two separate parts.
These and other objects have also been achieved according to the present invention by providing a connection for two hollow shaft sections of a drive shaft for a motor vehicle, comprising: a hollow shaft section to be coupled to a transmission of the motor vehicle, said hollow section being divided into two separate parts at an axial division proximate a location for a supporting bearing for the shaft section; and a connector for holding said two separate parts of the hollow shaft section together, said connector being threadedly engaged with a first of said two separate parts, said connector defining a sloped shoulder which engages a corresponding sloped shoulder of a second of said two separate parts.
These and other objects have also been achieved according to the present invention by providing a method of assembling a hollow drive shaft of a motor vehicle, said method comprising: coupling a first piece of a first hollow shaft section to a transmission of the motor vehicle; arranging a pivot bearing to support an end of the first piece of the first hollow shaft section located opposite said transmission; arranging a second piece of said first hollow shaft section in engagement with said first piece of said first hollow shaft section; inserting a connector into an interior of said first and second pieces, threadedly engaging said connector with said first piece such that a sloped shoulder of said connector abuttingly engages a sloped shoulder of said second piece; and coupling a second hollow shaft section to said first hollow shaft section with a disk joint interposed therebetween.
In the case of the solution of the invention, independently of a selection of material for the individual drive shaft components, the light-weight construction is achieved mainly by a skillful constructive combination of joints. By using a homokinetic joint with an integrated length compensation, a separate length compensation is not necessary. The possibility of mounting the center bearing is achieved by a closable axial shaft division--in the simplest case, by means of a friction welding. In the case of an elongated installation position, the center cardan joint may be constructed as a light-weight disk joint.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.